3 * Intel Management Engine Interface (Intel MEI) Linux driver
4 * Copyright (c) 2003-2012, Intel Corporation.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
20 #include <linux/types.h>
21 #include <linux/cdev.h>
22 #include <linux/poll.h>
23 #include <linux/mei.h>
24 #include <linux/mei_cl_bus.h>
29 #define MEI_RD_MSG_BUF_SIZE (128 * sizeof(u32))
32 * Number of Maximum MEI Clients
34 #define MEI_CLIENTS_MAX 256
37 * maximum number of consecutive resets
39 #define MEI_MAX_CONSEC_RESET 3
42 * Number of File descriptors/handles
43 * that can be opened to the driver.
45 * Limit to 255: 256 Total Clients
46 * minus internal client for MEI Bus Messages
48 #define MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)
52 MEI_FILE_UNINITIALIZED
= 0,
53 MEI_FILE_INITIALIZING
,
56 MEI_FILE_DISCONNECTING
,
57 MEI_FILE_DISCONNECT_REPLY
,
58 MEI_FILE_DISCONNECT_REQUIRED
,
59 MEI_FILE_DISCONNECTED
,
62 /* MEI device states */
64 MEI_DEV_INITIALIZING
= 0,
73 const char *mei_dev_state_str(int state
);
75 enum mei_file_transaction_states
{
82 * enum mei_cb_file_ops - file operation associated with the callback
84 * @MEI_FOP_WRITE: write
85 * @MEI_FOP_CONNECT: connect
86 * @MEI_FOP_DISCONNECT: disconnect
87 * @MEI_FOP_DISCONNECT_RSP: disconnect response
88 * @MEI_FOP_NOTIFY_START: start notification
89 * @MEI_FOP_NOTIFY_STOP: stop notification
91 enum mei_cb_file_ops
{
96 MEI_FOP_DISCONNECT_RSP
,
102 * enum mei_cl_io_mode - io mode between driver and fw
104 * @MEI_CL_IO_TX_BLOCKING: send is blocking
105 * @MEI_CL_IO_TX_INTERNAL: internal communication between driver and FW
107 * @MEI_CL_IO_RX_NONBLOCK: recv is non-blocking
109 enum mei_cl_io_mode
{
110 MEI_CL_IO_TX_BLOCKING
= BIT(0),
111 MEI_CL_IO_TX_INTERNAL
= BIT(1),
113 MEI_CL_IO_RX_NONBLOCK
= BIT(2),
117 * Intel MEI message data struct
119 struct mei_msg_data
{
124 /* Maximum number of processed FW status registers */
125 #define MEI_FW_STATUS_MAX 6
126 /* Minimal buffer for FW status string (8 bytes in dw + space or '\0') */
127 #define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))
131 * struct mei_fw_status - storage of FW status data
133 * @count: number of actually available elements in array
134 * @status: FW status registers
136 struct mei_fw_status
{
138 u32 status
[MEI_FW_STATUS_MAX
];
142 * struct mei_me_client - representation of me (fw) client
144 * @list: link in me client list
145 * @refcnt: struct reference count
146 * @props: client properties
147 * @client_id: me client id
148 * @tx_flow_ctrl_creds: flow control credits
149 * @connect_count: number connections to this client
150 * @bus_added: added to bus
152 struct mei_me_client
{
153 struct list_head list
;
155 struct mei_client_properties props
;
157 u8 tx_flow_ctrl_creds
;
166 * struct mei_cl_cb - file operation callback structure
168 * @list: link in callback queue
169 * @cl: file client who is running this operation
170 * @fop_type: file operation type
171 * @buf: buffer for data associated with the callback
172 * @buf_idx: last read index
173 * @fp: pointer to file structure
174 * @status: io status of the cb
175 * @internal: communication between driver and FW flag
176 * @blocking: transmission blocking mode
177 * @completed: the transfer or reception has completed
180 struct list_head list
;
182 enum mei_cb_file_ops fop_type
;
183 struct mei_msg_data buf
;
185 const struct file
*fp
;
193 * struct mei_cl - me client host representation
194 * carried in file->private_data
196 * @link: link in the clients list
197 * @dev: mei parent device
198 * @state: file operation state
199 * @tx_wait: wait queue for tx completion
200 * @rx_wait: wait queue for rx completion
201 * @wait: wait queue for management operation
202 * @ev_wait: notification wait queue
203 * @ev_async: event async notification
204 * @status: connection status
205 * @me_cl: fw client connected
206 * @fp: file associated with client
207 * @host_client_id: host id
208 * @tx_flow_ctrl_creds: transmit flow credentials
209 * @rx_flow_ctrl_creds: receive flow credentials
210 * @timer_count: watchdog timer for operation completion
211 * @notify_en: notification - enabled/disabled
212 * @notify_ev: pending notification event
213 * @tx_cb_queued: number of tx callbacks in queue
214 * @writing_state: state of the tx
215 * @rd_pending: pending read credits
216 * @rd_completed: completed read
218 * @cldev: device on the mei client bus
221 struct list_head link
;
222 struct mei_device
*dev
;
223 enum file_state state
;
224 wait_queue_head_t tx_wait
;
225 wait_queue_head_t rx_wait
;
226 wait_queue_head_t wait
;
227 wait_queue_head_t ev_wait
;
228 struct fasync_struct
*ev_async
;
230 struct mei_me_client
*me_cl
;
231 const struct file
*fp
;
233 u8 tx_flow_ctrl_creds
;
234 u8 rx_flow_ctrl_creds
;
239 enum mei_file_transaction_states writing_state
;
240 struct list_head rd_pending
;
241 struct list_head rd_completed
;
243 struct mei_cl_device
*cldev
;
246 #define MEI_TX_QUEUE_LIMIT_DEFAULT 50
247 #define MEI_TX_QUEUE_LIMIT_MAX 255
248 #define MEI_TX_QUEUE_LIMIT_MIN 30
251 * struct mei_hw_ops - hw specific ops
253 * @host_is_ready : query for host readiness
255 * @hw_is_ready : query if hw is ready
256 * @hw_reset : reset hw
257 * @hw_start : start hw after reset
258 * @hw_config : configure hw
260 * @fw_status : get fw status registers
261 * @pg_state : power gating state of the device
262 * @pg_in_transition : is device now in pg transition
263 * @pg_is_enabled : is power gating enabled
265 * @intr_clear : clear pending interrupts
266 * @intr_enable : enable interrupts
267 * @intr_disable : disable interrupts
268 * @synchronize_irq : synchronize irqs
270 * @hbuf_free_slots : query for write buffer empty slots
271 * @hbuf_is_ready : query if write buffer is empty
272 * @hbuf_max_len : query for write buffer max len
274 * @write : write a message to FW
276 * @rdbuf_full_slots : query how many slots are filled
278 * @read_hdr : get first 4 bytes (header)
279 * @read : read a buffer from the FW
283 bool (*host_is_ready
)(struct mei_device
*dev
);
285 bool (*hw_is_ready
)(struct mei_device
*dev
);
286 int (*hw_reset
)(struct mei_device
*dev
, bool enable
);
287 int (*hw_start
)(struct mei_device
*dev
);
288 void (*hw_config
)(struct mei_device
*dev
);
290 int (*fw_status
)(struct mei_device
*dev
, struct mei_fw_status
*fw_sts
);
291 enum mei_pg_state (*pg_state
)(struct mei_device
*dev
);
292 bool (*pg_in_transition
)(struct mei_device
*dev
);
293 bool (*pg_is_enabled
)(struct mei_device
*dev
);
295 void (*intr_clear
)(struct mei_device
*dev
);
296 void (*intr_enable
)(struct mei_device
*dev
);
297 void (*intr_disable
)(struct mei_device
*dev
);
298 void (*synchronize_irq
)(struct mei_device
*dev
);
300 int (*hbuf_free_slots
)(struct mei_device
*dev
);
301 bool (*hbuf_is_ready
)(struct mei_device
*dev
);
302 size_t (*hbuf_max_len
)(const struct mei_device
*dev
);
303 int (*write
)(struct mei_device
*dev
,
304 struct mei_msg_hdr
*hdr
,
305 const unsigned char *buf
);
307 int (*rdbuf_full_slots
)(struct mei_device
*dev
);
309 u32 (*read_hdr
)(const struct mei_device
*dev
);
310 int (*read
)(struct mei_device
*dev
,
311 unsigned char *buf
, unsigned long len
);
315 void mei_cl_bus_rescan_work(struct work_struct
*work
);
316 void mei_cl_bus_dev_fixup(struct mei_cl_device
*dev
);
317 ssize_t
__mei_cl_send(struct mei_cl
*cl
, u8
*buf
, size_t length
,
319 ssize_t
__mei_cl_recv(struct mei_cl
*cl
, u8
*buf
, size_t length
,
321 bool mei_cl_bus_rx_event(struct mei_cl
*cl
);
322 bool mei_cl_bus_notify_event(struct mei_cl
*cl
);
323 void mei_cl_bus_remove_devices(struct mei_device
*bus
);
324 int mei_cl_bus_init(void);
325 void mei_cl_bus_exit(void);
328 * enum mei_pg_event - power gating transition events
330 * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition
331 * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete
332 * @MEI_PG_EVENT_RECEIVED: the driver received pg event
333 * @MEI_PG_EVENT_INTR_WAIT: the driver is waiting for a pg event interrupt
334 * @MEI_PG_EVENT_INTR_RECEIVED: the driver received pg event interrupt
339 MEI_PG_EVENT_RECEIVED
,
340 MEI_PG_EVENT_INTR_WAIT
,
341 MEI_PG_EVENT_INTR_RECEIVED
,
345 * enum mei_pg_state - device internal power gating state
347 * @MEI_PG_OFF: device is not power gated - it is active
348 * @MEI_PG_ON: device is power gated - it is in lower power state
355 const char *mei_pg_state_str(enum mei_pg_state state
);
358 * struct mei_device - MEI private device struct
360 * @dev : device on a bus
361 * @cdev : character device
362 * @minor : minor number allocated for device
364 * @write_list : write pending list
365 * @write_waiting_list : write completion list
366 * @ctrl_wr_list : pending control write list
367 * @ctrl_rd_list : pending control read list
368 * @tx_queue_limit: tx queues per client linit
370 * @file_list : list of opened handles
371 * @open_handle_count: number of opened handles
373 * @device_lock : big device lock
374 * @timer_work : MEI timer delayed work (timeouts)
376 * @recvd_hw_ready : hw ready message received flag
378 * @wait_hw_ready : wait queue for receive HW ready message form FW
379 * @wait_pg : wait queue for receive PG message from FW
380 * @wait_hbm_start : wait queue for receive HBM start message from FW
382 * @reset_count : number of consecutive resets
383 * @dev_state : device state
384 * @hbm_state : state of host bus message protocol
385 * @init_clients_timer : HBM init handshake timeout
387 * @pg_event : power gating event
388 * @pg_domain : runtime PM domain
390 * @rd_msg_buf : control messages buffer
391 * @rd_msg_hdr : read message header storage
393 * @hbuf_depth : depth of hardware host/write buffer is slots
394 * @hbuf_is_ready : query if the host host/write buffer is ready
396 * @version : HBM protocol version in use
397 * @hbm_f_pg_supported : hbm feature pgi protocol
398 * @hbm_f_dc_supported : hbm feature dynamic clients
399 * @hbm_f_dot_supported : hbm feature disconnect on timeout
400 * @hbm_f_ev_supported : hbm feature event notification
401 * @hbm_f_fa_supported : hbm feature fixed address client
402 * @hbm_f_ie_supported : hbm feature immediate reply to enum request
403 * @hbm_f_os_supported : hbm feature support OS ver message
405 * @me_clients_rwsem: rw lock over me_clients list
406 * @me_clients : list of FW clients
407 * @me_clients_map : FW clients bit map
408 * @host_clients_map : host clients id pool
410 * @allow_fixed_address: allow user space to connect a fixed client
411 * @override_fixed_address: force allow fixed address behavior
413 * @reset_work : work item for the device reset
414 * @bus_rescan_work : work item for the bus rescan
416 * @device_list : mei client bus list
417 * @cl_bus_lock : client bus list lock
419 * @dbgfs_dir : debugfs mei root directory
421 * @ops: : hw specific operations
422 * @hw : hw specific data
429 struct list_head write_list
;
430 struct list_head write_waiting_list
;
431 struct list_head ctrl_wr_list
;
432 struct list_head ctrl_rd_list
;
435 struct list_head file_list
;
436 long open_handle_count
;
438 struct mutex device_lock
;
439 struct delayed_work timer_work
;
443 * waiting queue for receive message from FW
445 wait_queue_head_t wait_hw_ready
;
446 wait_queue_head_t wait_pg
;
447 wait_queue_head_t wait_hbm_start
;
452 unsigned long reset_count
;
453 enum mei_dev_state dev_state
;
454 enum mei_hbm_state hbm_state
;
455 u16 init_clients_timer
;
458 * Power Gating support
460 enum mei_pg_event pg_event
;
462 struct dev_pm_domain pg_domain
;
463 #endif /* CONFIG_PM */
465 unsigned char rd_msg_buf
[MEI_RD_MSG_BUF_SIZE
];
472 struct hbm_version version
;
473 unsigned int hbm_f_pg_supported
:1;
474 unsigned int hbm_f_dc_supported
:1;
475 unsigned int hbm_f_dot_supported
:1;
476 unsigned int hbm_f_ev_supported
:1;
477 unsigned int hbm_f_fa_supported
:1;
478 unsigned int hbm_f_ie_supported
:1;
479 unsigned int hbm_f_os_supported
:1;
481 struct rw_semaphore me_clients_rwsem
;
482 struct list_head me_clients
;
483 DECLARE_BITMAP(me_clients_map
, MEI_CLIENTS_MAX
);
484 DECLARE_BITMAP(host_clients_map
, MEI_CLIENTS_MAX
);
486 bool allow_fixed_address
;
487 bool override_fixed_address
;
489 struct work_struct reset_work
;
490 struct work_struct bus_rescan_work
;
492 /* List of bus devices */
493 struct list_head device_list
;
494 struct mutex cl_bus_lock
;
496 #if IS_ENABLED(CONFIG_DEBUG_FS)
497 struct dentry
*dbgfs_dir
;
498 #endif /* CONFIG_DEBUG_FS */
501 const struct mei_hw_ops
*ops
;
502 char hw
[0] __aligned(sizeof(void *));
505 static inline unsigned long mei_secs_to_jiffies(unsigned long sec
)
507 return msecs_to_jiffies(sec
* MSEC_PER_SEC
);
511 * mei_data2slots - get slots - number of (dwords) from a message length
512 * + size of the mei header
514 * @length: size of the messages in bytes
516 * Return: number of slots
518 static inline u32
mei_data2slots(size_t length
)
520 return DIV_ROUND_UP(sizeof(struct mei_msg_hdr
) + length
, 4);
524 * mei_slots2data - get data in slots - bytes from slots
526 * @slots: number of available slots
528 * Return: number of bytes in slots
530 static inline u32
mei_slots2data(int slots
)
536 * mei init function prototypes
538 void mei_device_init(struct mei_device
*dev
,
539 struct device
*device
,
540 const struct mei_hw_ops
*hw_ops
);
541 int mei_reset(struct mei_device
*dev
);
542 int mei_start(struct mei_device
*dev
);
543 int mei_restart(struct mei_device
*dev
);
544 void mei_stop(struct mei_device
*dev
);
545 void mei_cancel_work(struct mei_device
*dev
);
548 * MEI interrupt functions prototype
551 void mei_timer(struct work_struct
*work
);
552 void mei_schedule_stall_timer(struct mei_device
*dev
);
553 int mei_irq_read_handler(struct mei_device
*dev
,
554 struct list_head
*cmpl_list
, s32
*slots
);
556 int mei_irq_write_handler(struct mei_device
*dev
, struct list_head
*cmpl_list
);
557 void mei_irq_compl_handler(struct mei_device
*dev
, struct list_head
*cmpl_list
);
560 * Register Access Function
564 static inline void mei_hw_config(struct mei_device
*dev
)
566 dev
->ops
->hw_config(dev
);
569 static inline enum mei_pg_state
mei_pg_state(struct mei_device
*dev
)
571 return dev
->ops
->pg_state(dev
);
574 static inline bool mei_pg_in_transition(struct mei_device
*dev
)
576 return dev
->ops
->pg_in_transition(dev
);
579 static inline bool mei_pg_is_enabled(struct mei_device
*dev
)
581 return dev
->ops
->pg_is_enabled(dev
);
584 static inline int mei_hw_reset(struct mei_device
*dev
, bool enable
)
586 return dev
->ops
->hw_reset(dev
, enable
);
589 static inline int mei_hw_start(struct mei_device
*dev
)
591 return dev
->ops
->hw_start(dev
);
594 static inline void mei_clear_interrupts(struct mei_device
*dev
)
596 dev
->ops
->intr_clear(dev
);
599 static inline void mei_enable_interrupts(struct mei_device
*dev
)
601 dev
->ops
->intr_enable(dev
);
604 static inline void mei_disable_interrupts(struct mei_device
*dev
)
606 dev
->ops
->intr_disable(dev
);
609 static inline void mei_synchronize_irq(struct mei_device
*dev
)
611 dev
->ops
->synchronize_irq(dev
);
614 static inline bool mei_host_is_ready(struct mei_device
*dev
)
616 return dev
->ops
->host_is_ready(dev
);
618 static inline bool mei_hw_is_ready(struct mei_device
*dev
)
620 return dev
->ops
->hw_is_ready(dev
);
623 static inline bool mei_hbuf_is_ready(struct mei_device
*dev
)
625 return dev
->ops
->hbuf_is_ready(dev
);
628 static inline int mei_hbuf_empty_slots(struct mei_device
*dev
)
630 return dev
->ops
->hbuf_free_slots(dev
);
633 static inline size_t mei_hbuf_max_len(const struct mei_device
*dev
)
635 return dev
->ops
->hbuf_max_len(dev
);
638 static inline int mei_write_message(struct mei_device
*dev
,
639 struct mei_msg_hdr
*hdr
, const void *buf
)
641 return dev
->ops
->write(dev
, hdr
, buf
);
644 static inline u32
mei_read_hdr(const struct mei_device
*dev
)
646 return dev
->ops
->read_hdr(dev
);
649 static inline void mei_read_slots(struct mei_device
*dev
,
650 unsigned char *buf
, unsigned long len
)
652 dev
->ops
->read(dev
, buf
, len
);
655 static inline int mei_count_full_read_slots(struct mei_device
*dev
)
657 return dev
->ops
->rdbuf_full_slots(dev
);
660 static inline int mei_fw_status(struct mei_device
*dev
,
661 struct mei_fw_status
*fw_status
)
663 return dev
->ops
->fw_status(dev
, fw_status
);
666 bool mei_hbuf_acquire(struct mei_device
*dev
);
668 bool mei_write_is_idle(struct mei_device
*dev
);
670 #if IS_ENABLED(CONFIG_DEBUG_FS)
671 int mei_dbgfs_register(struct mei_device
*dev
, const char *name
);
672 void mei_dbgfs_deregister(struct mei_device
*dev
);
674 static inline int mei_dbgfs_register(struct mei_device
*dev
, const char *name
)
678 static inline void mei_dbgfs_deregister(struct mei_device
*dev
) {}
679 #endif /* CONFIG_DEBUG_FS */
681 int mei_register(struct mei_device
*dev
, struct device
*parent
);
682 void mei_deregister(struct mei_device
*dev
);
684 #define MEI_HDR_FMT "hdr:host=%02d me=%02d len=%d internal=%1d comp=%1d"
685 #define MEI_HDR_PRM(hdr) \
686 (hdr)->host_addr, (hdr)->me_addr, \
687 (hdr)->length, (hdr)->internal, (hdr)->msg_complete
689 ssize_t
mei_fw_status2str(struct mei_fw_status
*fw_sts
, char *buf
, size_t len
);
691 * mei_fw_status_str - fetch and convert fw status registers to printable string
693 * @dev: the device structure
694 * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
695 * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
697 * Return: number of bytes written or < 0 on failure
699 static inline ssize_t
mei_fw_status_str(struct mei_device
*dev
,
700 char *buf
, size_t len
)
702 struct mei_fw_status fw_status
;
707 ret
= mei_fw_status(dev
, &fw_status
);
711 ret
= mei_fw_status2str(&fw_status
, buf
, MEI_FW_STATUS_STR_SZ
);